A common type of emergency warning system for a vehicle is commonly called a “light bar.” Typically light bars are mounted to roofs of vehicles and wired to power sources in the engine compartments and controlled from control heads mounted in the passenger compartments.
Customer demands have driven light bars toward highly customizable designs. Manufacturers of light bars often start with a standard housing and then offer an array of alternative types of lighting devices to populate the interior of the light bar. For example, customers may ask for different mixes of takedown lights and alley lights, whose functions are suggested by their names. Customers may also ask for lights of different colors and different types of light sources such as light emitting diodes (LEDs), halogen lights, strobes or even lasers. Furthermore, the lighting assemblies may be fixed, rotating or oscillating.
To accommodate the demands of customers, the interiors of light bars are typically designed to provide flexibility for substituting different lighting devices as specified by the customer. Often the interior spaces of light bars house an assortment of individual light assemblies and wires to each assembly with associated connectors, making the interiors densely packed with complex wiring schemes.
These designs have evolved into highly complex interiors that are time consuming to assemble and tend to discourage automation of the assembly. Because the manufacturing process remains dependent on manual assembly, there is a higher than desirable risk of errors in the manufacturing process.
In addition to presenting manufacturing challenges, the multiple connections in the wiring schemes of the interior spaces of light bars create points of potential mechanical and electrical failure. Multiple individual wire connectors may fail because of vibration, the stress of temperature cycling, accidental tensioning of the wire during assembly or repair and other common sources of wear and tear. Servicing these many mechanical connections disrupts service and gives rise to reliability issues. Also, service requirements add expense to the light bar.